The jam session at the Penny Lane Music Emporium in Fort Lauderdale is probably one of the few musical gatherings in South Florida where senior citizens and teenagers play out of the same songbook.

About 20 people of all ages stand or sit in a circle, strumming ukuleles. Each of them has one eye on the sheet music, the other on their host, Ty Olopai.

“Beginners, when they pick it up, learn music in a minute,” says Olopai.

Olopai is the founder of the Florida Ukulele Network — or F.U.N. for short. He started the nonprofit about five years ago. Its original six members used to play together at Olopai’s local Starbucks until the group outgrew the space. The network now boasts about 500 members.

Olopai is also the chief organizer of the Ukulele Fest South Florida, a two-day event featuring workshops and performances by nationally known ukulele artists. This year’s festival starts Friday at ArtServe in Fort Lauderdale.